21422203405 has 4 divisors (see below), whose sum is σ = 25706644092. Its totient is φ = 17137762720.

The previous prime is 21422203399. The next prime is 21422203417. The reversal of 21422203405 is 50430222412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5876602281 + 15545601124 = 76659^2 + 124682^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21422203405 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21422203405.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2142220336 + ... + 2142220345.

It is an arithmetic number, because the mean of its divisors is an integer number (6426661023).

Almost surely, 2^21422203405 is an apocalyptic number.

It is an amenable number.

21422203405 is a deficient number, since it is larger than the sum of its proper divisors (4284440687).

21422203405 is an equidigital number, since it uses as much as digits as its factorization.

21422203405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4284440686.

The product of its (nonzero) digits is 3840, while the sum is 25.

Adding to 21422203405 its reverse (50430222412), we get a palindrome (71852425817).

The spelling of 21422203405 in words is "twenty-one billion, four hundred twenty-two million, two hundred three thousand, four hundred five".